232 W. L. RUSSELL AND E. F. OAKBERG 



it seems clear that tlie main cause for the shortening of the reproductive life- 

 span is partial destruction of the pool of oocytes. 



Here, then, is a late somatic effect of irradiation that has been traced 

 back to the immediate damage, which is simply early ceU killing. This 

 suggests that serious consideration should be given to the possibility that the 

 cellular basis for some of the other apparently complex late effects of irra- 

 diation may also trace back to nothing more mysterious than cell death 

 immediately following irradiation. 



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Murray, J. M. (1931). Amer. J. Roentgenol. 25, 1. 



Oakberg, E. F. (1960). Suppl. to J. Dairy Sci. 43, 54. 



Oakberg, E. F. (1962). Proc. Soc. exp. Biol., N.Y. 109, 763. 



Oakberg, E. F., and Clark, E. (1961a), Amer. Zoologist 1, 465. 



Oakberg, E. F., and Clark, E. (1961b). J. cell. comp. Physiol. Suppl. 1, 58, 173. 



Russell, L. B., Stelzner, K. F., and Russell, W. L. (1959a). Proc. Soc. exp. Biol., N. Y. 



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 ScHUGT, P. (1928). Strahlentherapie 27, 603. 



